Apparatus for charging and cleaning boreholes by means of compressed air



1930- c. HERDEMERTEN APPARATUS FOR CHARGING AND CLEANING BOREHOLES BYMEANS OF COMPRESSED AIR Filed May 1927 n v e n for Carl Herdemer/enPatented Feb. 11, 1930 UNITED STATES PATENT oFncE CARL HEBDEMERT EN, OFNIEDERSCHREIBERHAU, GERMANY, ASSIGNOR TO FIRM; nmnmx ACT.-GES., OIBERLIN, GERMANY APPARATUS FOR CHARGING AND CLEANING BOBEHOLES BY MEANSOF COMPRESSED AIR Application filed May 9, 1927. Serial No. 190,121.

For charging bore-holes to be used for blasting-workinmining operationsapparatus are used having the material to be forced into the bore-hole,generally rock-dust, enclosed in a storage-receptacle from which thepulverulent material is forced into the bore-hole by means of compressedair, said receptacle being connected up to a compressed-air vessel orother supplying means. There 1s formed in the said receptacle a separatecompartment by means of a perforated wall, and the compressed air isintroduced into th1s compartment.

The fact has been ascertained that the effect of apparatus of the kindstated in the preceding paragraph is not so perfect as desired as, owingto the compressed air acting solely by pressing or shoving, a part ofthe pulverulent material, or of the rock-dust respectively, is againdriven out of the boreole.

The object of the present invention is to obviate the drawbackmentioned, and I attain the effect desired by designing the apparatus insuch a manner that the compressed air exerts not only a pressing, butalso a suckmg action upon the rock-dust. The means to at tain thistwo-fold efi'ect consists therein that the compressed-air compartment inthe apparatus or, more precisely, the perforated Wall mentioned, isprovided with some separate perforations also at the narrowest portionof the rock-dust receptacle where this latter is connected with the pipeleading the as dust to and into the bore-hole, the position of saidseparate perforations being such that the currents of compressed airstreaming through them escape practically directly into said pipe, andthe effect. belng, therefore,

40 practically like that of an in]ector. The rockdust into which thecompressed air is forced through the main perforations of the wall, andwhich is, besides, sub eCt-ed to the pressure of the compressed air, isthus, sucked out of the rock-dust receptacle by the separateperforations mentioned, and the bore-hole is now charged in a perfectlyreliable manner, without any loss of the rock dust.

The apparatus improved 1n the manner stated can, however, be used alsofor clearing the bore-holes in order either to remove the rock-duststill present in the hole, or the charge of the hole in the case of afailure. As the dust often times contains also quartz it may easilyoccur that sparks are produced at the bore-hole by the tube, the simpleblowing out With a compressed-air pipe is, therefore, inadmissible.

Now, in order to render the apparatus suited also for the blowing-outoperation, with complete prevention of the arising of sparks, it isprovided with a separate guide-tube, the diameter of which correspondsabout to that of the bore-hole, in such a manner, that said guide-tubecan be shoved thereinto; besides, the said tube consists of a soft metalso that no sparks can arise when it is scratched at and by the wall ofthe bore-hole. The dust present in this hole slides no more along thewall of the same but-is driven out by the compressed air through thatguide-tube. A basin arranged outside the guide-tube near the front endof the some intercepts the dust, gathers it and causes it to fall downto the bottom or into any suitable vessel.

The invention is illustrated diagram matically and by way of example onthe accompanying drawing on which Figure l is an axial section throughan apparatus designed according to this invention, and Figure 2 ispartly a side-view of this apparatus and partly an axial section througha bore hole with the said guide-tube therein, in connection with a fewother parts, this figure being drawn to a reduced scale.

On the drawing, a denotes the body of the apparatus, which is preferablyfunnel-shaped and provided with a suitable cover. In the example shown 0denotes this cover and b a tightening rubber-ring which can be pressedupon the edge of the neck of the body or vessel a by means of a somewhatbowshaped member 6 e hinged at d to a bracket r afiixed to the top ofthe vessel (1., extending over the cover a, and forming at its free enda hook e which co-operates with a bow f hinged to a grip-forming lever gfulcrumed at g to a bracket .9 also aflixed to the top of the vessel a.

A perforated sheet-metal member h of trough-like cross-section isinserted into the vessel a and secured to the wall of the same and formswith the respective wall portion a compartment h. The member h isrovided with perforations h and the wal portion concerned is providedwith a nozzle m into which a cock m is inserted. The nozzle m' in thewall portion instead of inthe membar h's A particularly importantfeature resides, now, in the provision of separate perforations islocated at the end a of the com artment a and having such a positionthat t e currents of com ressed air escaping through them stream fbrth'practically directly into the discharge pipe i which is, preferably,curved, as shown.

The pipe 1' can be connected with an extension pipe i (Fig. 2)surrounded with a larger pipe 0, the diameter of which is 'ust a littlesmaller than the diameter of the ore hole n, and which is detachablyattached to the pipe 27 by means of narrow stays 0'. The tube 0 consistsof a soft metal, for instance zinc, so that no sparks can arise when itis shoved into the bore-hole n. In front of the tube 0 a basin p isafiixed to the pipe i, as shown in Fig. 2.

The tube o is not required when the rock dust is introduced into thebore-hole. When the dust has been introduced into the vessel a theconnected tubes i and i are introduced into the bore-hole, and the cockm is opened so that the compressed air streams first into the comartment h and then further through the per orations h"- into the vessela where it acts u n the rock-dust in the manner already descri d. Thecom ressed air streams, however, also through t e separate perforationsk and sucks the dust through the passage a, drivin it then through t epipes z and z" into t e bore-hole. The pipes i and i are withdrawn byand by accordin to the progress in the filling of the boreole, and therocedure is continued until the borehole as been filled in the desireddegree.-

When then, later on, the bore-hole is to be cleaned or the charge mustbe removed because of a failure, the tube 0 is shoved upon the tube 0',and compressed air is again blown into the bore-hole, the vessel a beingnow, however, empty- The dust is then blown by the compressed airissuing forth from the tube 1" into the tube 0 and towards and a ainstOWIlcomprising, in combination, a receptacle adapted receive theulverulent filling ma-,

terial for the bore-ho es, means for sup lying the compressed air tosaid mate in said vessel, as well as to the discharge aperture of thelatter, a tube extending forth from said discharge a rture and adaptedto be introduced into a re-hole, and another tube encompassing thefirst-mentioned tube and forming a tubular passage between itself andsaid first-mentioned tube and havin an outer diameter just fitting intoa boreole, substantially as set fort 2. An ap aratus for charging andcleaning bore holes y means of compressed air comprisin in combination,a receptacle ada ted to receive the pulverulent filling materia for thebore-holes, means for supplyin the compressed air to said material insai vessel, as well as to the discharge a erture of the latter, a tubeextendin forth from said discharge aperture and a apted to be introducedinto a bore-hole; and another tube consisting of a soft metal unable toproduce sparks, and encompassin the first-mentioned tube and forming atu ular gassage between itself and said first-mentione tube and havin anouter diameter just fitting into a boreole, substantially as set forth.

3. An ap aratus for charging and cleaning bore holes y means ofcompressed air, comprising, in combination, a receptacle ada ted torecelve the pulverluent filling materia for the bore-holes, means forsupplyin the compressed air to said material in sai vessel, as well asto the discharge a erture of the latter, a tube extendin forth rom saiddischarge aperture and a a ted to be introduced into a bore-hole; anoter tube encompassin the first-mentioned tube and formi'n a tu ular passae between itself and sai tione tube and having an outer diameter justfitting into a bore-hole, and a basin arranged upon the inner tube infront of the outer one, substantially and for the purpose set forth.

In testimony whereof I aflix m 31 ature. CARL HERDE TEN.

first-men

